Baby monitor reduces caesareans

A new foetal monitoring device has been designed that will measure oxygen supply to the baby during labour and could cut the caesarean rate by up to half.

The University of Queensland said its preliminary studies indicate that the new method, called 'foetal intrapartum pulse oximetry', is safer and more accurate than current methods.

The new system differs from existing monitoring systems in that it measures the amount of oxygen being supplied to the foetus rather than the foetal heart rate. Oxygen is the critical factor in foetal distress, according to Professor Colditz, Professor of Perinatal Medicine at the Royal Women's Hospital in Brisbane.

Monitoring heart rate is problematic because babies' rates vary so much. Professor Colditz said the normal foetal heart range is 110 - 160, but a variety of foetal heart rate patterns within and outside that range are difficult to interpret. Caesarian rates have doubled since obstetricians began monitoring babies' heartrates.

"There is no way of distinguishing between a heart rate related to distress and a normal rate for that individual baby, so a caesarean is usually performed if the rate is even slightly questionable," he said.

Adult oxygen monitors work by fastening a sensor to a finger, and measuring the differential response of two light waves passed through the blood filled tissue. However, getting access to a baby's finger is very difficult. Instead, doctors put the sensor disc up through the cervix and place it against the cheek of the baby.

Paul Colditz, Professor of Perinatal Medicine at the Royal Women's Hospital in Brisbane said controlled hospital trials would be done in women's hospitals in Queensland and Victoria.